英语表示倍数：four times as many ...than ...到底是几倍?

英语表示倍数：four times as many ...than ...到底是几倍?例句：Using techniques to track the birth of new neurons,researchers found that mice fed a high-fat diet make four times as many new cells in the hypothalamus than do animals raised on standard chow.这里到底是“多4倍”还是“4倍”的意思?我个人理解这是一个省略-倒装句,调整后的语序为：Using techniques to track the birth of new neurons,researchers found that mice fed a high-fat diet make four times as many new cells in the hypothalamus (more) than animals (which were) raised on standard chow do.